System and method for laser assisted sample transfer to solution for chemical analysis

Abstract

A system and method for laser desorption of an analyte from a specimen and capturing of the analyte in a suspended solvent to form a testing solution are described. The method can include providing a specimen supported by a desorption region of a specimen stage and desorbing an analyte from a target site of the specimen with a laser beam centered at a radiation wavelength (λ). The desorption region is transparent to the radiation wavelength (λ) and the sampling probe and a laser source emitting the laser beam are on opposite sides of a primary surface of the specimen stage. The system can also be arranged where the laser source and the sampling probe are on the same side of a primary surface of the specimen stage. The testing solution can then be analyzed using an analytical instrument or undergo further processing.

What is claimed is: 
     
       1. A system for extracting an analyte from a specimen, comprising:
 a specimen stage comprising a desorption region that is transparent to a radiation wavelength (λ); 
 a sampling probe for delivering a solvent to a position above said specimen stage, for statically suspending the solvent above said specimen stage, and for removing the solvent from the specimen stage; and 
 a laser source for emitting a laser beam centered at said radiation wavelength (λ) toward said specimen stage, wherein said laser source and said sampling probe are on opposite sides of a primary surface of said specimen stage. 
 
     
     
       2. The system according to  claim 1 , further comprising a focusing lens between said laser source and said specimen stage for focusing said laser beam. 
     
     
       3. The system according to  claim 1 , further comprising: an analytical instrument for determining a chemical composition of an analyte in a testing solution comprising said solvent. 
     
     
       4. The system according to  claim 3 , wherein said solvent is in fluid communication with said analytical instrument. 
     
     
       5. The system according to  claim 3 , wherein said analytical instrument is a mass spectrometer, an ionization source, a separation method, or a combination thereof. 
     
     
       6. The system according to  claim 1 , further comprising a stepper mechanism configured to sequentially direct said laser beam at a plurality of target sites of a specimen supported by said specimen stage. 
     
     
       7. The system according to  claim 6 , wherein said stepper mechanism is further configured to provide relative motion between said specimen stage and said sampling probe. 
     
     
       8. The system according to  claim 7 , further comprising a testing device, wherein said stepper mechanism is configured (i) to sequentially position said sampling probe to capture an analyte that is laser desorbed from each of a plurality of target sites with a suspended solvent to form a testing solution and (ii) to discharge said testing solution to said testing device. 
     
     
       9. The system according to  claim 8 , wherein said testing solution is discharged from a distal end of said sampling probe. 
     
     
       10. A method of extracting an analyte from a specimen, comprising:
 providing a specimen supported by a desorption region of a specimen stage; 
 desorbing an analyte from a target site of a specimen with a laser beam centered at a radiation wavelength (λ); and 
 delivering a solvent to a position above the specimen stage, statically suspending the solvent above the specimen stage, capturing said desorbed analyte with the statically suspended solvent to form a testing solution, and removing the testing solution from a position above the specimen stage, wherein said delivering, suspending, and removing steps are performed with a sampling probe, and wherein said desorption region is transparent to said radiation wavelength (λ), and wherein said specimen and a laser source emitting said laser beam are on opposite sides of a primary surface of said specimen stage. 
 
     
     
       11. The method according to  claim 10 , further comprising analyzing a chemical composition of said desorbed analyte. 
     
     
       12. The method according to  claim 11 , further comprising:
 repeating the desorbing, capturing and analyzing steps for each of a plurality of target sites of said specimen. 
 
     
     
       13. The method according to  claim 12 , further comprising plotting a property of a chemical component for each of said plurality of target sites.